Prepare the Cookie Dough: Cream together the unsalted butter and granulated sugar until light and fluffy. Add in the eggs and vanilla extract, mixing well. Gradually incorporate the all-purpose flour and baking powder until a soft dough forms.

Chill and Roll Out: Wrap the dough in plastic wrap and chill in the refrigerator for at least 30 minutes. Once chilled, roll it out on a floured surface to about ¼ inch thickness.

Cut and Bake: Cut out mini circles for your clock faces using cookie cutters and place them on a baking sheet lined with parchment paper. Bake in a preheated oven at 350°F for 8-10 minutes, until the edges are lightly golden.

Cool Cookies: Let the cookies cool on a wire rack until completely cooled.

Make Royal Icing: In a mixing bowl, combine powdered sugar, egg whites (or meringue powder), and a splash of water. Beat until stiff peaks form. Adjust with additional water as needed.

Decorate: Divide the royal icing into bowls, tinting each with desired food coloring. Outline and fill in the cookies with icing, allowing them to dry for several hours or overnight.

Draw Clocks: Once the icing is dry, use a food coloring pen to draw clock hands on each cookie.